Tensions in the Middle East and north Africa, we are told, lie behind the recent increase in global fuel prices, which Wednesday hit a 2 ?-year high. Yet while Brent crude this week stayed above $120 a barrel, in Tripoli petrol hovered at around 34p a gallon. And that is not a typo. The popular reason for why those closest to the fighting, in this case, suffer less than those farther afield, is Libya’s hefty subsidies. The less popular reason is that world energy markets have been carefully designed to profit from the slightest supply hiccup, even if there is little evidence of actual shortages.

The energy-trading fraternity has never let the facts get in the way of a good supply scare. True, this historically fragile market is vulnerable?to price swings as demand threatens to climb faster than production. But there is more to it than that. Indeed, what President Barack Obama did not mention last week in his energy security speech about the faults of the global energy market could fill a Saudi oilfield.

Rising from the ashes of a failed potato exchange in downtown Manhattan, the modern-day oil market came to prominence in the 1980s. Its main architect was Michel Marks, the Paris-born son of a produce merchant, who to this day is none too happy with how his creation turned out. Over time, the market has mushroomed to include futures, options and swaps contracts traded on a handful of exchanges round the world. There is also a thriving private, over-the-counter market, where physical “wet” barrels change hands. Today, the oil market’s global daily value comes to about $600bn, even if limited transparency means exact figures remain elusive. The central market for oil is now part of the Chicago Mercantile Exchange, although it is making inroads into London in an apparent effort to escape new US rules under the Dodd-Frank act.